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Which Fish Get To Recolonize After Elwha’s Dams Are Gone?

May 9, 2013 | KUOW
CONTRIBUTED BY:
Ashley Ahearn

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  • Field technicians with the Lower Elwha Klallam Tribe catch steelhead in a murky side channel near the mouth of the Elwha and prepare them to be transferred into pristine habitat above the former site of the lower dam. credit: Ashley Ahearn
  • An overhead view photographed with the help of a drone in 2012 shows what the heavy flush of sediment has done to muddy the lower reaches of the Elwha River. credit: Provided by the U.S. Geological Survey
  • Construction crews redirected the channel of the Elwha River during the deconstruction of the lower dam. This was taken in January, 2012, about four months after the project began. credit: Katie Campbell
Field technicians with the Lower Elwha Klallam Tribe catch steelhead in a murky side channel near the mouth of the Elwha and prepare them to be transferred into pristine habitat above the former site of the lower dam. | credit: Ashley Ahearn | rollover image for more

This is the second in a two-part series.

From where Mike McHenry stands he can see several gray, torpedo-shaped bodies moving slowly through the brown water of this side channel of the Elwha River, not too far from the site of the largest dam removal project in U.S. history.

“You are looking at several wild winter steelhead. These are the native remnant stock of the Elwha River,” explains McHenry, the Lower Elwha Klallam Tribe’s fisheries habitat biologist.

These fish are some of the last wild steelhead in the Elwha - biologists estimate that there are between 200 and 300 left, and they’re here to spawn. But despite the fact that tearing down two dams has opened nearly 70 miles of pristine habitat on the upper Elwha River and its tributaries in the Olympic National Park, it’s made life rather difficult for fish in this river right now.

Millions of cubic yards of sediment and debris are flowing down from above the two dams, making this murky lower stretch of the river a bad place to spawn. But nevertheless, these few wild fish represent the prospect of a restored river, populated with thousands of salmon and steelhead – rivaling the numbers of fish that were here before the dams went in 100 years ago.

With that future in mind, McHenry and a team of field biologists and technicians are capturing, tagging and relocating these ready-to-spawn steelhead into a clear tributary of the Elwha, above the former site of the lower dam.

It’s a fascinating scene, filled with silvery flailing and splashing and men carrying fish from the pool up the hill to the waiting tanks to be anesthetized and tagged before the drive to the drop-off point upstream.

Then all that activity is brought to a halt by a slightly sleepy steelhead resting in a tank. It’s captured the attention of John McMillan, a contract biologist with the National Oceanic and Atmospheric Administration.

“This is probably broodstock,” McMillan says.

Broodstock is another term for fish used by hatcheries for breeding purposes.

Given the way broodstock programs are operated on the Elwha River, McMillan says this particular steelhead was probably the offspring of wild parents. But it’s clear it had spent time in a hatchery.

“The fish chew on each other’s fins in the hatchery and they end up with a permanently stubbed dorsal,” McMillan explains, extending the steelhead’s dorsal fin in his hands. “On this one we’re not sure, but in the wild fish you almost never see the front rays of the dorsal all bent.”

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A broodstock fish discovered among wild steelhead. Credit: Ashley Ahearn

This moment of discovery symbolizes a much larger debate playing out as different groups struggle over how best to rebuild the Elwha’s fish runs.

The Great Hatchery Debate

The 20th century wasn’t just an era of dam building in the Northwest. It’s also when hatcheries went up along the region’s rivers to supplement wild populations reduced by those dams, among other causes.

Some Native Americans support hatchery use as a way to restore fish runs that provided subsistence for earlier generations before the dams. But there are some who think hatcheries should not be used to speed up the return of wild, native fish.

It’s not just tribes that favor hatcheries on the Elwha as a way to provide a safe haven to keep native-origin steelhead alive in the tumultuous conditions that have accompanied dam removal.

Elwha hatchery fish
Juvenile fish in 2011 at the Lower Elwha Hatchery.
Credit: Katie Campbell.

“In this case what is very clear, crystal clear to us, is that the fish are in such bad shape and the conditions in the river are so unprecedented that any risk that the hatchery poses to these fish is more than outweighed by the benefits,” says Rob Jones, chief of production for inland fisheries with the National Marine Fisheries Service – one of the defendants in a lawsuit to stop the use of fish hatcheries on the Elwha.

Jones says wild steelhead numbers are dangerously low in the Elwha so the hatchery is necessary to steelhead survival. “The job is to help them hang on until these conditions improve enough and then, the strategy is, as we see that improvement that we start to phase out the hatchery.”

Jones says the hatcheries will be phased out when salmon and steelhead numbers increase, but the Elwha River Fish Restoration Plan does not give a set timeframe or hard date when the hatcheries will be removed.

Small-Brained Fish Or The JV Team?

Research has shown that when some types of salmon and steelhead are raised in hatcheries they can become domesticated. Other research suggests hatchery fish’s brains don’t grow as big and steelhead hatchery fish don’t produce as many offspring once they’re released. They’re also less likely to survive to adulthood than wild fish. But as the two hatcheries on the Elwha have demonstrated for years now, they’re a way to ensure that fish return to the river when conditions are hostile for wild, native fish.

The lawsuit over hatcheries in the Elwha recovery plan is a measure of how staunchly some groups oppose them.

“We believe that wild fish in the Elwha would recover better in the absence of hatchery influence,” says Jamie Glasgow, director of science and research for the Wild Fish Conservancy. “You cannot raise a fish in a hatchery without having a negative impact on it’s genetics and its behavior.”

The Wild Fish Conservancy is one of the non-profits that filed the lawsuit against the Lower Elwha Klallam Tribe, the National Marine Fisheries Service and several governmental agencies responsible for the Elwha restoration project.

The group says that hatcheries aren’t necessary for fish recovery in the Elwha, but if hatcheries are going to beallowed, it should only be for a limited time.

“From our perspective the plan lacks teeth,” says Glasgow. “It does not give us assurance and a real commitment to when hatchery production will be stopped.”

But keep in mind, the recovery process, underway on the Elwha right now, is unlike anything scientists have ever encountered. It is truly a grand experiment. No government or tribe has ever tried anything like this before - and no one knows exactly how it will play out.

Here’s the central question: with so few wild salmon and steelhead in the Elwha, should hatchery fish like be used as sort of junior varsity subs to boost the overall numbers of fish in this river as it recovers post-dam removal?

The science isn’t settled on how hatcheries impact wild fish, though there’s been a debate among fisheries managers on that for years.

Right now the Elwha is a difficult place to live if you’re a salmon or steelhead but it’s not impossible. Last year 500 wild chinook made the journey above the lower dam to spawn on their own.

‘We Need To Make A Decision’

The debate over hatchery use in the Elwha recovery is playing out in real time as Mike McHenry stands over the tank and looks down at the fish with the nibbled dorsal fin that John McMillan has singled out as possibly coming from the nearby hatchery.

“Here’s where we need to make a decision,” he says, looking at McMillan.

Do the biologists bring these hatchery fish up into the pristine habitat above the dam? Or do they leave them here?

The team decides to bring two hatchery-raised fish upstream, along with six wild steelhead, to be released into the newly-available habitat above the former site of the lower dam.

McHenry leans down into the cold clear waters of this side creek and unzips a black bag. Two large steelhead slip slowly into the shadows along the bank nearby.

The biologists have DNA samples from all of the fish they’re releasing today – hatchery and wild. Mike McHenry and John McMillan say that will allow them to see who spawned with whom and which pairings led to more successful offspring.

“It’s a mixture, and that’s what we have,” McHenry says. McMillan nods his head in agreement.

“Yeah. It’s all we have to work with and you figure nature will sort it out ultimately. Nature sorts out who wins and who loses — and it will.”

For now anyway, nature is getting a little bit of help in the natural selection process.

Wednesday: Elwha River Recovery Proceeds Despite Sediment Setbacks.

© 2013 KUOW
Lower Elwha Klallam Tribe hatchery salmon steelhead Elwha Dam Removal
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